Layered honeycomb intermetallic phases have attracted considerable research interest due to the wide array of exciting physical properties inherent in these materials.Here,we follow the evolution in structure and elec...Layered honeycomb intermetallic phases have attracted considerable research interest due to the wide array of exciting physical properties inherent in these materials.Here,we follow the evolution in structure and electronic properties of a relatively unexplored material system,Sr_(1−x)Ca_(x)PdAs,as the hexagonal PdAs honeycomb layer in SrPdAs distorts into the orthorhombic CaPdAs structure.The Sr-rich compounds(x=0 to 1/3)form symmetric,hexagonal honeycomb PdAs layers,whereas in the Ca-rich region(x=1/2 to 1)the PdAs layers distort into an orthorhombic structure featuring long and short Pd–Pd distances.This dis tortion occurs when the average Pd–Pd distance falls below 4.21Å.All compounds are observed to exhibit metallic temperature-dependent resistivity trends.There are no apparent discontinuities indicative of metal-to-insulator transitions and the room temperature resistivity values range from 18 to 180 mΩcm.In total,this work maps out the structural and electronic phase diagram of Sr_(1−x)Cax PdAs compounds.展开更多
基金supported by the Center for Emergent Materials,an NSF-funded MRSEC under award no.DMR-1420451Partial support for transport measurements by M.R.S.was provided by AFOSR project no.FA9550-18-1-0335+1 种基金J.E.G.acknowledges the Camille and Henry Dreyfus Foundation for partial support.D.W.gratefully acknowledges the financial support by the German Science Foundation DFG Research Fellowship(WE6480/1)Y.W.and W.W.thank the Ohio Supercomputer Center for computer time under grant PAS0072.
文摘Layered honeycomb intermetallic phases have attracted considerable research interest due to the wide array of exciting physical properties inherent in these materials.Here,we follow the evolution in structure and electronic properties of a relatively unexplored material system,Sr_(1−x)Ca_(x)PdAs,as the hexagonal PdAs honeycomb layer in SrPdAs distorts into the orthorhombic CaPdAs structure.The Sr-rich compounds(x=0 to 1/3)form symmetric,hexagonal honeycomb PdAs layers,whereas in the Ca-rich region(x=1/2 to 1)the PdAs layers distort into an orthorhombic structure featuring long and short Pd–Pd distances.This dis tortion occurs when the average Pd–Pd distance falls below 4.21Å.All compounds are observed to exhibit metallic temperature-dependent resistivity trends.There are no apparent discontinuities indicative of metal-to-insulator transitions and the room temperature resistivity values range from 18 to 180 mΩcm.In total,this work maps out the structural and electronic phase diagram of Sr_(1−x)Cax PdAs compounds.
